Automatic firearm having a breech block with front and rear cartridge driving means



Nov. 26, 1968 H. MENNEKING 3,412,642

AUTOMATIC FIREARM HAVING A BREECH BLOCK WITH FRONT I AND REAR CARTRIDGE DRIVING MEANS Filed Jan. 24, 1967 2 Sheets-Sheet 1 FIG] iii

INVENTOR.

1mm ,7- MEN/v6 KING Efren/mils 1968 H. MENNEKING 3,412,642

AUTOMATIC FIREARM HAVING A BREECH BLOCK WITH FRONT AND REAR CARTRIDGE DRIVING MEANS Filed Jan. 24, 1967 2 Sheets-Sheet 2 FIGA l N VEN TOR.

Hair/nu? melwvkluo RTTOA NE K5 United States Patent 3 Claims. 61. 89-33) ABSTRACT OF THE DISCLOSURE A pivotal automatic firearm, more especially a machine gun, comprising a trunnion bearing in the vicinity of the cartridge feed means which is provided at the rear end of the firearm housing so as to keep the pivot radius required behind the firearm from the trunnion to the rear edge of the firearm small, the breech block having at its front and rear ends drivers such that when the breech block advances the cartridge is brought into an intermediate position by the rear driver, from which position it is introduced into the cartridge chamber by the front driver on the next advance.

This invention relates to an automatic firearm more especially a machine gun, comprising a sliding breech block. In such weapons, the cartridges are brought into the breech path of the firearm by feed means (belt feed or magazine) and introduced from this position into the cartridge chamber of the firearm iby the advancing breech block.

In the case of pivotal firearms mounted in trunnions, the trunnion bearings are usually arranged in the vicinity of the cartridge feed means so as to keep the pivot path of the cartridge belt connected to the weapon as small as possible. However, this has the disadvantage that a large space is required behind the trunnion mounting, and this space is not always available, particularly in the case of firearms built into armoured vehicles or revolving gun 'mounts, without involving correspondingly large dimenslons.

It is the primary object of this invention to provide a pivotal firearm wherein the length from the center of the cartridge feed means to the rear edge of the weapon is kept comparatively very small, so that the pivot radius required behind the weapon from the trunnions to the rear edge of the weapon or cradle is also small.

According to the present invention, this problem is solved in that the cartridge feed means are provided at the rear end of the firearm housing, and that the breech block carries at its front and rear ends drivers such that when the breech block advances the cartridge is brought into an intermediate position by the rear driver, from which position it is introduced into the cartridge chamber by the front driver on the next advance.

In accordance with this invention the arrangement may be such that the cartridge is held in the two positions so as to be resilient perpendicularly to the plane of feed, or such that the drivers are resilient in this plane. The breech block and the drivers can thus slide very easily past under the cartridge in the intermediate position and the cartridge in the feed means.

The present invention affords various advantageous possibilities in gun mounts, both in revolving mounts and in armoured cupolas, as well as in infantry gun mounts for single, twin and multiple weapons, in that the trunnions may be disposed further to the rear and the firearm thus displaced further forwards, creating a 3,412,642 Patented Nov. 26, 1968 larger operating space behind the firearm which allows an additional weapon to be built in if necessary or the dimensions of the cupola or gun mount to be kept smaller and thus alford a smaller target.

In firearms built into armoured cupolas, this invention results in further advantages as regards the ejection of the cartridge cases and the sealing problems involved therewith. Shifting the firearm 'forwards now makes it possible to eject the cartridge cases in front of the armoured cupola, so that special deflection walls or caseejection chutes, which are always difiicult to seal from the inside of the armoured cupola, are obviated.

The trunnions may also be disposed behind the firearm, making gun mountings possible in which the high degree of twisting of the cartridge belt arising hitherto when shooting in the upper angular range and frequently leading to failure in the cartridge feed is obviated.

Some of the objects and advantages of this invention having been stated, others will appear as the description proceeds when taken in connection with the accompanying drawings, in which:

FIGURE 1 is a partial view of a firearm constructed according to the invention, shown partly in section with the breech block open;

FIGURE 2 is a partial view similar to FIG. 1 with the breech block closed;

FIGURE 3 is a partial view of another embodiment of the 'weapon according to the invention with a short breech block;

FIGURE 4 is a side view of an automatic firearm with the ammunition feed in the region of the trunnion mounting;

FIGURE 5 is also a side view of the firearm shown in FIG. 4, but with the ammunition feed according to the invention.

Referring now more particularly to the drawings, FIG. 1 shows an automatic firearm and the cartridge chamber 2 thereof arranged at the rear end of the barrel. The reference numeral 3 denotes the breech block, which slides in the breech path. Provided at the rear end of the firearm are cartridge feed means 4, which may be of the type as disclosed in United States Patents 3,000,265 and 3,230,828 and which are mounted to be pivotal about one of the longitudinal edges thereof on the mount of the weapon in a manner not illustrated, so that they can be pivoted laterally thereof. The drive of the cartridge feed means 4 may be of any type; it may be effected by recoiling parts of the firearm, by the pressure of gas taken from the barrel or by an outside source of power.

At its rear end, the breech block comprises a driver 5 which is mounted to be resilient in the vertical plane and which, as can be seen from FIG. 1, when the breech block is open engages by means of a nose 6 a cartridge 7 supplied from the feed means.

When the breech block advances, the cartridge 7 is pushed by the driver 5 out of the feed means and brought into the position b shown in FIG. 2, the next cartridge being brought into position a by the feed means at the same time. On return of the breech block, the driver 5 whose nose comprises an inclined edge 8, is pressed down by the cartridge so that the breech block can slide past under said cartridge. Provided at the front end of the breech block is a driver 9 which acts in similar manner and which, when the breech block advances again, introduces the cartridge conveyed into the position b into the cartridge chamber of the firearm in known manner. The driver 9 of the breech bolt 3 may be designed as a spring-urged loading pawl of a well-known type as described in United States Patent 3,000,265. The arrangement may be such that the cartridges are held rigidly in the positions a and b; in this case, the drivers must be arranged yieldably, i.e. resiliently. It is, however, also possible to hold the cartridges resiliently perpendicularly to the plane of feed, so that the drivers may be arranged rigidly on the breech block. A combination of these features may also be realised, or the construction may be such that one driver is rigid and the other resilient.

FIG. 3 now show the invention in a weapon having a very short breech block. The invention may also be applied with advantage in this case, particularly in weapons which are vertically pivotal about a trunnion disposed behind the firearm. The rear driver 5 is arranged in this case on an arm 10 which is secured to the breech body and which projects rearwardly beyond the latter. The feed of the cartridges and the loading operation are exactly the same in this case as was described in connection with FIGS. 1 and 2.

FIG. 5 shows in comparison with FIG. 4 the smaller pivot radius obtainable with the invention in weapons mounted in trunnion bearings. FIG. 4 shows a firearm 1 having a belt feed device 4, in which the cartridges are introduced by the breech block directly into the cartridge chamber of the weapon. The trunnion bearing 11 is arranged at the level of the bore axis at the center of the belt means. The pivot radius necessary behind the firearm from the axis of the trunnion bearing to the rear edge of the weapon is R In contrast, FIG. 5 shows the com paratively small pivot radius R which can be achieved with the invention.

In the drawings and specifications there have been set forth preferred embodiments of the invention and, al-

though specific terms are employed, they are used in a generic and descriptive sense only and not for purposes of limitation, the scope of the invention being defined in the claims.

What is claimed is:

1. An automatic firearm comprising housing means, cartridge chamber means, cartridge feed means at the rear end of said housing means, sliding breech block means adapted for receiving a cartridge from said cartridge feed means and conveying means into said cartridge chamber means, said breech block means including front driver means, located at the front end of said breech block means, and a rear driver means, located at the rear end of said breech block means, and breech block means having a length of approximately half the length of the path of travel of a cartridge from said cartridge feed means to said cartridge chamber means, said rear driver means receiving a cartridge from said cartridge feed means and conveying same to an intermediate position as said front driver means receives the preceding cartridge at said intermediate position and conveys said preceding cartridge to said cartridge chamber means and introduces said preceding cartridge therein, said front driver means and said rear driver means positioned in a substantially axial path between said cartridge feed means and said cartridge chamber means.

2. An automatic firearm according to claim 1, further comprising a rearwardly-extending arm, one end of said arm being secured near the rear end of said breech block means, the other end of said arm supporting said rear driver means.

3. An automatic firearm according to claim 1, wherein said front driver means and said rear driver means include abutment members having nose portions at their respective leading edges, the nose portions being resiliently supported on said breech block means for motion in a plane at substantially right angles to the path of travel of the cartridge.

References Cited UNITED STATES PATENTS 317,161 5/1885 Maxim 89-33 X 891,778 6/1908 Mertens 89-33 X 2,113,202 4/1938 Stange 89--33 2,997,307 8/1961 Fuhrman 8933 X BENJAMIN A. BORCHELT, Primary Examiner.

STEPHEN C. BENTLEY, Assistant Examiner.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3,412,642 November 26, 1968 Hartmut Menneking It is certified that error appears in the above identified patent and that said Letters Patent are hereby corrected as shown below:

Column 3, line 40, "means" should read same Signed and sealed this 31st day of March 1970.

(SEAL) Attest:

Edward M. Fletcher, Jr.

WILLIAM E. SCHUYLER, JR. 

